Image upload dialog OK button disabled after error message (Flash off)

To reproduce:

• Go to images
• Add an image...
• In the upload dialog browse for an image that is too large to pass image validation
• Click OK
  Expected: An error message appears, and other files can be selected for upload
  Actual: An error message appears, but the OK button is and stays disabled. The dialog needs to be closed and reopened again to be able to upload files.